[PATCH v2 2/9] x86/shadow: drop hash_vcpu_foreach()

[Jan Beulich <jbeulich@xxxxxxxx>]

The domain based variant is easily usable by shadow_audit_tables(); all
that's needed is conversion of the callback functions.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Acked-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>

--- a/xen/arch/x86/mm/shadow/common.c
+++ b/xen/arch/x86/mm/shadow/common.c
@@ -1640,59 +1640,11 @@ bool shadow_hash_delete(struct domain *d
     return true;
 }
 
-typedef int (*hash_vcpu_callback_t)(struct vcpu *v, mfn_t smfn, mfn_t 
other_mfn);
 typedef int (*hash_domain_callback_t)(struct domain *d, mfn_t smfn, mfn_t 
other_mfn);
 
 #define HASH_CALLBACKS_CHECK(mask) \
     BUILD_BUG_ON((mask) > (1U << ARRAY_SIZE(callbacks)) - 1)
 
-static void hash_vcpu_foreach(struct vcpu *v, unsigned int callback_mask,
-                              const hash_vcpu_callback_t callbacks[],
-                              mfn_t callback_mfn)
-/* Walk the hash table looking at the types of the entries and
- * calling the appropriate callback function for each entry.
- * The mask determines which shadow types we call back for, and the array
- * of callbacks tells us which function to call.
- * Any callback may return non-zero to let us skip the rest of the scan.
- *
- * WARNING: Callbacks MUST NOT add or remove hash entries unless they
- * then return non-zero to terminate the scan. */
-{
-    int i, done = 0;
-    struct domain *d = v->domain;
-    struct page_info *x;
-
-    ASSERT(paging_locked_by_me(d));
-
-    /* Can be called via p2m code &c after shadow teardown. */
-    if ( unlikely(!d->arch.paging.shadow.hash_table) )
-        return;
-
-    /* Say we're here, to stop hash-lookups reordering the chains */
-    ASSERT(d->arch.paging.shadow.hash_walking == 0);
-    d->arch.paging.shadow.hash_walking = 1;
-
-    for ( i = 0; i < SHADOW_HASH_BUCKETS; i++ )
-    {
-        /* WARNING: This is not safe against changes to the hash table.
-         * The callback *must* return non-zero if it has inserted or
-         * deleted anything from the hash (lookups are OK, though). */
-        for ( x = d->arch.paging.shadow.hash_table[i]; x; x = next_shadow(x) )
-        {
-            if ( callback_mask & (1 << x->u.sh.type) )
-            {
-                ASSERT(x->u.sh.type <= SH_type_max_shadow);
-                ASSERT(callbacks[x->u.sh.type] != NULL);
-                done = callbacks[x->u.sh.type](v, page_to_mfn(x),
-                                               callback_mfn);
-                if ( done ) break;
-            }
-        }
-        if ( done ) break;
-    }
-    d->arch.paging.shadow.hash_walking = 0;
-}
-
 static void hash_domain_foreach(struct domain *d,
                                 unsigned int callback_mask,
                                 const hash_domain_callback_t callbacks[],
@@ -3211,7 +3163,7 @@ int shadow_domctl(struct domain *d,
 void shadow_audit_tables(struct vcpu *v)
 {
     /* Dispatch table for getting per-type functions */
-    static const hash_vcpu_callback_t callbacks[SH_type_unused] = {
+    static const hash_domain_callback_t callbacks[SH_type_unused] = {
 #if SHADOW_AUDIT & (SHADOW_AUDIT_ENTRIES | SHADOW_AUDIT_ENTRIES_FULL)
 # ifdef CONFIG_HVM
         [SH_type_l1_32_shadow] = SHADOW_INTERNAL_NAME(sh_audit_l1_table, 2),
@@ -3258,7 +3210,7 @@ void shadow_audit_tables(struct vcpu *v)
     HASH_CALLBACKS_CHECK(SHADOW_AUDIT & (SHADOW_AUDIT_ENTRIES |
                                          SHADOW_AUDIT_ENTRIES_FULL)
                          ? SHF_page_type_mask : 0);
-    hash_vcpu_foreach(v, mask, callbacks, INVALID_MFN);
+    hash_domain_foreach(v->domain, mask, callbacks, INVALID_MFN);
 }
 
 #ifdef CONFIG_PV
--- a/xen/arch/x86/mm/shadow/multi.c
+++ b/xen/arch/x86/mm/shadow/multi.c
@@ -326,32 +326,32 @@ static void sh_audit_gw(struct vcpu *v,
     if ( mfn_valid(gw->l4mfn)
          && mfn_valid((smfn = get_shadow_status(d, gw->l4mfn,
                                                 SH_type_l4_shadow))) )
-        (void) sh_audit_l4_table(v, smfn, INVALID_MFN);
+        sh_audit_l4_table(d, smfn, INVALID_MFN);
     if ( mfn_valid(gw->l3mfn)
          && mfn_valid((smfn = get_shadow_status(d, gw->l3mfn,
                                                 SH_type_l3_shadow))) )
-        (void) sh_audit_l3_table(v, smfn, INVALID_MFN);
+        sh_audit_l3_table(d, smfn, INVALID_MFN);
 #endif /* PAE or 64... */
     if ( mfn_valid(gw->l2mfn) )
     {
         if ( mfn_valid((smfn = get_shadow_status(d, gw->l2mfn,
                                                  SH_type_l2_shadow))) )
-            (void) sh_audit_l2_table(v, smfn, INVALID_MFN);
+            sh_audit_l2_table(d, smfn, INVALID_MFN);
 #if GUEST_PAGING_LEVELS >= 4 /* 32-bit PV only */
         if ( mfn_valid((smfn = get_shadow_status(d, gw->l2mfn,
                                                  SH_type_l2h_shadow))) )
-            (void) sh_audit_l2_table(v, smfn, INVALID_MFN);
+            sh_audit_l2_table(d, smfn, INVALID_MFN);
 #endif
     }
     if ( mfn_valid(gw->l1mfn)
          && mfn_valid((smfn = get_shadow_status(d, gw->l1mfn,
                                                 SH_type_l1_shadow))) )
-        (void) sh_audit_l1_table(v, smfn, INVALID_MFN);
+        sh_audit_l1_table(d, smfn, INVALID_MFN);
     else if ( (guest_l2e_get_flags(gw->l2e) & _PAGE_PRESENT)
               && (guest_l2e_get_flags(gw->l2e) & _PAGE_PSE)
               && mfn_valid(
               (smfn = get_fl1_shadow_status(d, guest_l2e_get_gfn(gw->l2e)))) )
-        (void) sh_audit_fl1_table(v, smfn, INVALID_MFN);
+        sh_audit_fl1_table(d, smfn, INVALID_MFN);
 #endif /* SHADOW_AUDIT & SHADOW_AUDIT_ENTRIES */
 }
 
@@ -3950,9 +3950,8 @@ static const char *sh_audit_flags(const
     return NULL;
 }
 
-int cf_check sh_audit_l1_table(struct vcpu *v, mfn_t sl1mfn, mfn_t x)
+int cf_check sh_audit_l1_table(struct domain *d, mfn_t sl1mfn, mfn_t x)
 {
-    struct domain *d = v->domain;
     guest_l1e_t *gl1e, *gp;
     shadow_l1e_t *sl1e;
     mfn_t mfn, gmfn, gl1mfn;
@@ -4019,7 +4018,7 @@ int cf_check sh_audit_l1_table(struct vc
     return done;
 }
 
-int cf_check sh_audit_fl1_table(struct vcpu *v, mfn_t sl1mfn, mfn_t x)
+int cf_check sh_audit_fl1_table(struct domain *d, mfn_t sl1mfn, mfn_t x)
 {
     guest_l1e_t *gl1e, e;
     shadow_l1e_t *sl1e;
@@ -4045,9 +4044,8 @@ int cf_check sh_audit_fl1_table(struct v
     return 0;
 }
 
-int cf_check sh_audit_l2_table(struct vcpu *v, mfn_t sl2mfn, mfn_t x)
+int cf_check sh_audit_l2_table(struct domain *d, mfn_t sl2mfn, mfn_t x)
 {
-    struct domain *d = v->domain;
     guest_l2e_t *gl2e, *gp;
     shadow_l2e_t *sl2e;
     mfn_t mfn, gmfn, gl2mfn;
@@ -4097,9 +4095,8 @@ int cf_check sh_audit_l2_table(struct vc
 }
 
 #if GUEST_PAGING_LEVELS >= 4
-int cf_check sh_audit_l3_table(struct vcpu *v, mfn_t sl3mfn, mfn_t x)
+int cf_check sh_audit_l3_table(struct domain *d, mfn_t sl3mfn, mfn_t x)
 {
-    struct domain *d = v->domain;
     guest_l3e_t *gl3e, *gp;
     shadow_l3e_t *sl3e;
     mfn_t mfn, gmfn, gl3mfn;
@@ -4145,9 +4142,8 @@ int cf_check sh_audit_l3_table(struct vc
     return 0;
 }
 
-int cf_check sh_audit_l4_table(struct vcpu *v, mfn_t sl4mfn, mfn_t x)
+int cf_check sh_audit_l4_table(struct domain *d, mfn_t sl4mfn, mfn_t x)
 {
-    struct domain *d = v->domain;
     guest_l4e_t *gl4e, *gp;
     shadow_l4e_t *sl4e;
     mfn_t mfn, gmfn, gl4mfn;
--- a/xen/arch/x86/mm/shadow/multi.h
+++ b/xen/arch/x86/mm/shadow/multi.h
@@ -83,19 +83,19 @@ SHADOW_INTERNAL_NAME(sh_remove_l3_shadow
 #if SHADOW_AUDIT & SHADOW_AUDIT_ENTRIES
 int cf_check
 SHADOW_INTERNAL_NAME(sh_audit_l1_table, GUEST_LEVELS)
-    (struct vcpu *v, mfn_t sl1mfn, mfn_t x);
+    (struct domain *d, mfn_t sl1mfn, mfn_t x);
 int cf_check
 SHADOW_INTERNAL_NAME(sh_audit_fl1_table, GUEST_LEVELS)
-    (struct vcpu *v, mfn_t sl1mfn, mfn_t x);
+    (struct domain *d, mfn_t sl1mfn, mfn_t x);
 int cf_check
 SHADOW_INTERNAL_NAME(sh_audit_l2_table, GUEST_LEVELS)
-    (struct vcpu *v, mfn_t sl2mfn, mfn_t x);
+    (struct domain *d, mfn_t sl2mfn, mfn_t x);
 int cf_check
 SHADOW_INTERNAL_NAME(sh_audit_l3_table, GUEST_LEVELS)
-    (struct vcpu *v, mfn_t sl3mfn, mfn_t x);
+    (struct domain *d, mfn_t sl3mfn, mfn_t x);
 int cf_check
 SHADOW_INTERNAL_NAME(sh_audit_l4_table, GUEST_LEVELS)
-    (struct vcpu *v, mfn_t sl4mfn, mfn_t x);
+    (struct domain *d, mfn_t sl4mfn, mfn_t x);
 #endif
 
 extern const struct paging_mode